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面向海南自贸港建设的MTA人才“双跨融合”培养模式研究
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作者 郭强 王秋娜 《研究生教育研究》 北大核心 2024年第1期86-93,共8页
发展专业学位研究生教育是主动服务创新型国家建设,为国家区域发展战略提供高层次应用型人才支撑的重要路径。海南省旅游管理硕士专业学位(以下简称“MTA”)人才培养应和海南自由贸易港“三区一中心”的重大战略同频共振,分类分层次培... 发展专业学位研究生教育是主动服务创新型国家建设,为国家区域发展战略提供高层次应用型人才支撑的重要路径。海南省旅游管理硕士专业学位(以下简称“MTA”)人才培养应和海南自由贸易港“三区一中心”的重大战略同频共振,分类分层次培养具有地域化特色明显、专业能力与实践能力强、跨界融合与跨文化融合特性突出、能够创造性从事海南自由贸易港建设实际工作的高级应用型人才。针对海南省MTA人才培养中现存的问题,构建MTA双跨融合教育共同体,提出共育自贸港特色专业群、共建跨界融通课程体系、共享专业师资团队、共创生产实践平台、共筑分类分层次培养计划等MTA人才培养创新路径,实现教育链、人才链、产业链、创新链之间的有机融合。 展开更多
关键词 双跨融合 教育共同体 旺工淡学 自由贸易港 mta
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iRoot BP plus与MTA根尖屏障术治疗年轻恒牙慢性根尖周炎的疗效比较
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作者 孙艳妮 赵蕾 +1 位作者 刘伟 殷晓萍 《上海口腔医学》 CAS 2024年第3期260-264,共5页
目的:探讨iRoot BP plus与MTA根尖屏障术治疗年轻恒牙慢性根尖周炎的效果。方法:将122例年轻恒牙慢性根尖周炎患者随机分为试验组(n=61,患牙61颗)和对照组(n=61,患牙61颗),试验组行iRoot BP plus根尖屏障术,对照组行MTA根尖屏障术,比较... 目的:探讨iRoot BP plus与MTA根尖屏障术治疗年轻恒牙慢性根尖周炎的效果。方法:将122例年轻恒牙慢性根尖周炎患者随机分为试验组(n=61,患牙61颗)和对照组(n=61,患牙61颗),试验组行iRoot BP plus根尖屏障术,对照组行MTA根尖屏障术,比较2组患者术后3、6、9、12个月的旧根尖周指数(old periapical index,O-PAI)、根尖透射区面积、疗效、治疗次数、炎症因子水平。采用SPSS 19.0软件包对数据进行统计学分析。结果:术后12个月,试验组和对照组的O-PAI评级为(1.48±0.36)、(1.71±0.42),根尖透射区面积为(0.51±0.14)、(1.09±0.31),2组O-PAI评级和根尖透射区面积相比差异显著(P<0.05)。术后3、6、12个月,2组患者的O-PAI评级逐渐降低(P<0.05),根尖透射区面积逐渐减少(P<0.05)。术后12个月,试验组和对照组的成功率为98.36%、88.52%,组间差异显著(P<0.05)。试验组和对照组患者的治疗次数为(3.64±0.58)、(4.72±0.61)次,组间差异显著(P<0.05)。术后3个月,试验组和对照组患者的血清hs-CRP水平为(6.89±1.13)、(7.25±1.40)mg/L,与治疗前相比差异显著(P<0.05);治疗3个月后,试验组和对照组患者的血清IL-6水平为(82.04±19.62)、(87.52±20.85)mg/L,与治疗前相比差异显著(P<0.05)。2组患者治疗前、后的血清IL-6、hs-CRP水平组间相比,差异无显著性(P>0.05)。结论:iRoot BP plus根尖屏障术治疗年轻恒牙慢性根尖周炎有助于降低O-PAI指数,减少术后就诊次数,术后成功率更高。 展开更多
关键词 根尖屏障术 iRoot BP plus mta 年轻恒牙 根尖周炎
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比较生物陶瓷材料iRoot BP Plus和MTA形成根尖屏障修复根尖未发育完全恒牙的效果分析 被引量:1
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作者 岳亚瑞 《罕少疾病杂志》 2024年第1期123-124,共2页
目的比较生物陶瓷材料iRoot BP Plus和无机三氧化物聚合物(MTA)形成根尖屏障修复根尖未发育完全恒牙的效果。方法回顾2018年1月至2022年8月医院牙体牙髓专家门诊收治的80例(80颗患牙)根尖未发育完全恒牙患者,按材料差异应用差异分为两... 目的比较生物陶瓷材料iRoot BP Plus和无机三氧化物聚合物(MTA)形成根尖屏障修复根尖未发育完全恒牙的效果。方法回顾2018年1月至2022年8月医院牙体牙髓专家门诊收治的80例(80颗患牙)根尖未发育完全恒牙患者,按材料差异应用差异分为两组,A组40例:根尖屏障修复术中应用iRoot BP Plus材料;B组40例:术中应用MTA材料;对比两组修复效果。结果A组、B组效果评价比较(P>0.05)。A组充填操作时间(8.51±1.38)min,短于B组的(15.48±2.09)min,差异有统计学意义(P<0.05)。A组治疗6个月O-PAI评分低于B组,并发症发生率2.50%低于B组的20.00%(P<0.05)。结论iRoot BP Plus和MTA形成根尖屏障修复根尖未发育完全恒牙均有相似效果,但iRoot BP Plus充填时间短,并发症少,值得应用。 展开更多
关键词 iRoot BP Plus mta 根尖屏障修复术 根尖未发育完全恒牙
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MTA2、SET8蛋白在喉癌中的表达及与临床病理特征的关系
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作者 张子梓 程慧娟 郭改改 《实用癌症杂志》 2024年第5期705-709,共5页
目的探讨MTA2、SET8蛋白在喉癌中的表达及与临床病理特征的关系。方法收集喉癌患者205例作为研究对象,采用免疫组织化学染色法检测MTA2、SET8阳性蛋白,采用Real-time PCR检测MTA2、SET8 mRNA表达水平。分析MTA2、SET8蛋白表达与喉癌患... 目的探讨MTA2、SET8蛋白在喉癌中的表达及与临床病理特征的关系。方法收集喉癌患者205例作为研究对象,采用免疫组织化学染色法检测MTA2、SET8阳性蛋白,采用Real-time PCR检测MTA2、SET8 mRNA表达水平。分析MTA2、SET8蛋白表达与喉癌患者临床病理特征的关系。Spearson相关性分析MTA2蛋白与SET8蛋白表达之间的关系。结果喉癌组MTA2、SET8蛋白阳性表达率(56.10%、54.15%)显著高于癌旁组,差异均有统计学意义(χ^(2)=27.926,P<0.001;χ^(2)=28.277,P<0.001);喉癌组MTA2、SET8 mRNA表达水平高于癌旁组,差异均具有统计学意义(t=25.005,P<0.001;t=20.390,P<0.001)。喉癌组织中MTA2、SET8蛋白阳性表达与性别、年龄、是否吸烟、临床分型均无关(P>0.05),与淋巴结是否转移、病理分级、临床分期有关(P<0.05)。Spearson相关性分析显示,MTA2蛋白与SET8蛋白表达呈现正相关(γ=0.477,P<0.05)。结论MTA2、SET8蛋白在喉癌中表达明显上升,且与喉癌的发展密切相关,预示其可能成为诊断分子的潜能。 展开更多
关键词 mta2 SET8 喉癌 临床病理特征
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MTA,iRoot BP Plus和nRoot BP修补髓底穿孔封闭性体外研究
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作者 张艳丽 肖海波 +1 位作者 陶慧敏 陈巧 《口腔医学研究》 CAS CSCD 北大核心 2024年第1期51-55,共5页
目的:评价3种材料Mineral trioxide aggregate(MTA)、iRoot BP Plus和nRoot BP修复磨牙髓底穿孔的封闭能力及边缘适应性。方法:收集符合标准的恒磨牙62颗,开髓、制备髓底穿孔后随机分为3个实验组(n=18),A组(MTA组)、B组(iRoot BP Plus组... 目的:评价3种材料Mineral trioxide aggregate(MTA)、iRoot BP Plus和nRoot BP修复磨牙髓底穿孔的封闭能力及边缘适应性。方法:收集符合标准的恒磨牙62颗,开髓、制备髓底穿孔后随机分为3个实验组(n=18),A组(MTA组)、B组(iRoot BP Plus组)、C组(nRoot BP)和2个对照组(n=4),D组(阳性对照组)、E组(阴性对照)。从3个实验组中各随机选4个样本用扫描电子显微镜观察髓室底与修复材料间间隙宽度。剩余样本在1%的碱性品红溶液中浸泡48 h,用染料渗透法检测评估修复部位的封闭效果。结果:A、B、C三组染料渗透差异有统计学意义(P<0.05)。MTA比iRoot BP Plus、nRoot BP的染料穿透性更大。扫描电镜下,iRootBP Plus、nRootBP与髓室底间的间隙宽度小于MTA,3组间差异有统计学意义(P<0.05)。结论:iRootBP Plus和nRootBP在修补髓底穿孔时展示了较好的封闭性和边缘适应性。 展开更多
关键词 mta 生物陶瓷 髓室底穿孔 封闭性
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Underwater Pulse Waveform Recognition Based on Hash Aggregate Discriminant Network
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作者 WANG Fangchen ZHONG Guoqiang WANG Liang 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期654-660,共7页
Underwater pulse waveform recognition is an important method for underwater object detection.Most existing works focus on the application of traditional pattern recognition methods,which ignore the time-and space-vary... Underwater pulse waveform recognition is an important method for underwater object detection.Most existing works focus on the application of traditional pattern recognition methods,which ignore the time-and space-varying characteristics in sound propagation channels and cannot easily extract valuable waveform features.Sound propagation channels in seawater are time-and space-varying convolutional channels.In the extraction of the waveform features of underwater acoustic signals,the effect of high-accuracy underwater acoustic signal recognition is identified by eliminating the influence of time-and space-varying convolutional channels to the greatest extent possible.We propose a hash aggregate discriminative network(HADN),which combines hash learning and deep learning to minimize the time-and space-varying effects on convolutional channels and adaptively learns effective underwater waveform features to achieve high-accuracy underwater pulse waveform recognition.In the extraction of the hash features of acoustic signals,a discrete constraint between clusters within a hash feature class is introduced.This constraint can ensure that the influence of convolutional channels on hash features is minimized.In addition,we design a new loss function called aggregate discriminative loss(AD-loss).The use of AD-loss and softmax-loss can increase the discriminativeness of the learned hash features.Experimental results show that on pool and ocean datasets,which were collected in pools and oceans,respectively,by using acoustic collectors,the proposed HADN performs better than other comparative models in terms of accuracy and mAP. 展开更多
关键词 convolutional channel hash aggregate discriminative network aggregate discriminant loss waveform recognition
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Clinical significance of platelet mononuclear cell aggregates in patients with sepsis and acute respiratory distress syndrome
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作者 Chong-Min Huang Juan-Juan Li Wei-Ke Wei 《World Journal of Clinical Cases》 SCIE 2024年第5期966-972,共7页
BACKGROUND The diagnosis of sepsis combined with acute respiratory distress syndrome(ARDS)has increased owing to the enhanced awareness among medical profes-sionals and the continuous development of modern medical tec... BACKGROUND The diagnosis of sepsis combined with acute respiratory distress syndrome(ARDS)has increased owing to the enhanced awareness among medical profes-sionals and the continuous development of modern medical technologies,while early diagnosis of ARDS still lacks specific biomarkers.One of the main patho-genic mechanisms of sepsis-associated ARDS involves the actions of various pathological injuries and inflammatory factors,such as platelet and white blood cells activation,leading to an increase of surface adhesion molecules.These adhesion molecules further form platelet-white blood cell aggregates,including platelet-mononuclear cell aggregates(PMAs).PMAs has been identified as one of the markers of platelet activation,here we hypothesize that PMAs might play a potential biomarker for the early diagnosis of this complication.METHODS We selected 72 hospitalized patients diagnosed with sepsis as the study population between March 2019 and March 2022.Among them,30 patients with sepsis and ARDS formed the study group,while 42 sepsis patients without ARDS comprised the control group.After diagnosis,venous blood samples were imme-diately collected from all patients.Flow cytometry was employed to analyze the expression of PMAs,platelet neutrophil aggregates(PNAs),and platelet aggregates(PLyAs)in the serum.Additionally,the Acute Physiology and Chronic Health Evaluation(APACHE)II score was calculated for each patient,and receiver operating characteristic curves were generated to assess diagnostic value.RESULTS The study found that the levels of PNAs and PLyAs in the serum of the study group were higher than those in the control group,but the difference was not statistically significant(P>0.05).However,the expression of PMAs in the serum of the study group was significantly upregulated(P<0.05)and positively correlated with the APACHE II score(r=0.671,P<0.05).When using PMAs as a diagnostic indicator,the area under the curve value was 0.957,indicating a high diagnostic value(P<0.05).Furthermore,the optimal cutoff value was 8.418%,with a diagnostic sensitivity of 0.819 and specificity of 0.947.CONCLUSION In summary,the serum levels of PMAs significantly increase in patients with sepsis and ARDS.Therefore,serum PMAs have the potential to become a new biomarker for clinically diagnosing sepsis complicated by ARDS. 展开更多
关键词 SEPSIS Acute respiratory distress syndrome Platelet leukocyte aggregates Platelet mononuclear cell aggregates Biomarker
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Mechanical Behavior Based on Aggregates Microstructure of Ultra-high Performance Concrete
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作者 丁庆军 ZHOU Changsheng +4 位作者 张高展 GUO Hong LI Yang ZHANG Yongyuan GUO Kaizheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期673-681,共9页
We developed ultra-high performance concrete(UHPC)incorporating mullite sand and brown corundum sand(BCS),and the quartz sand UHPC was utilized to prepare for comparison.The properties of compressive strength,elastic ... We developed ultra-high performance concrete(UHPC)incorporating mullite sand and brown corundum sand(BCS),and the quartz sand UHPC was utilized to prepare for comparison.The properties of compressive strength,elastic modulus,ultrasonic pulse velocity,flexural strength,and toughness were investigated.Scanning electron microscopy and nanoindentation were also conducted to reveal the underlying mechanisms affecting macroscopic performance.Due to the superior interface bonding properties between mullite sand and matrix,the compressive strength and flexural toughness of UHPC have been significantly improved.Mullite sand and BCS aggregates have higher stiffness than quartz sand,contributing to the excellent elastic modulus exhibited by UHPC.The stiffness and volume of aggregates have a more significant impact on the elastic modulus of UHPC than interface performance,and the latter contributes more to the strength of UHPC.This study will provide a reference for developing UHPC with superior elastic modulus for structural engineering. 展开更多
关键词 ultra-high performance concrete mechanical properties fine aggregates MICROSTRUCTURE NANOINDENTATION
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Straw mulching alters the composition and loss of dissolved organic matter in farmland surface runoff by inhibiting the fragmentation of soil small macroaggregates
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作者 Shanshan Cai Lei Sun +7 位作者 Wei Wang Yan Li Jianli Ding Liang Jin Yumei Li Jiuming Zhang Jingkuan Wang Dan Wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1703-1717,共15页
Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How st... Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How straw mulching affects the composition and loss of runoff DOM by changing soil aggregates remains largely unclear.Here,a straw mulching treatment was compared to a no mulching treatment(as a control)on sloping farmland with black soil erosion in Northeast China.We divided the soil into large macroaggregates(>2 mm),small macroaggregates(0.25-2 mm),and microaggregates(<0.25 mm).After five rain events,the effects of straw mulching on the concentration(characterized by dissolved organic carbon(DoC)and composition(analyzed by fluorescence spectroscopy)of runoff and soil aggregate DOM were studied.The results showed that straw mulching reduced the runoff amount by 54.7%.Therefore,although straw mulching increased the average DOc concentration in runoff,it reduced the total runoff DOM loss by 48.3%.The composition of runoff DOM is similar to that of soil,as both contain humic-like acid and protein-like components.With straw mulching treatment,the protein-like components in small macroaggregates accumulated and the protein-like components in runoff declined with rain events.Fluorescence spectroscopy technology may help in understanding the hydrological paths of rain events by capturing the dynamic changes of runoff and soil DOM characteristics.A variation partitioning analysis(VPA)indicated that the DOM concentration and composition of microaggregates explained 68.2%of the change in runoff DOM from no mulching plots,while the change in runoff DOM from straw mulching plots was dominated by small macroaggregates at a rate of 55.1%.Taken together,our results demonstrated that straw mulching reduces the fragmentation of small macroaggregates and the loss of microaggregates,thus effecting DOM compositions in soil and reducing the DOM loss in runoff.These results provide a theoretical basis for reducing carbon loss in sloping farmland. 展开更多
关键词 dissolved organic matter black soil surface runoff aggregateS fluorescence spectrum
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High-efficiency Carbonation Modification Methods of Recycled Coarse Aggregates
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作者 张美香 YANG Xiaolin +3 位作者 丁亚红 SUN Bo ZHANG Xianggang LÜXiuwen 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期386-398,共13页
To solve the problem of only surface carbonation and realize high-efficiency carbonation of recycled coarse aggregate,the method of carbonated recycled coarse aggregate with nano materials pre-soaking was first put fo... To solve the problem of only surface carbonation and realize high-efficiency carbonation of recycled coarse aggregate,the method of carbonated recycled coarse aggregate with nano materials pre-soaking was first put forward.The carbonation effect of modified recycled coarse aggregate with three different carbonation methods was evaluated,and water absorption,apparent density and crush index of modified recycled coarse aggregate were measured.Combined with XRD,SEM,and MIP microscopic analysis,the high-efficiency carbonation strengthening mechanism of modified recycled coarse aggregate was revealed.The experimental results show that,compared with the non-carbonated recycled coarse aggregate,the physical and microscopic properties of carbonated recycled coarse aggregate are improved.The method of carbonation with nano-SiO_(2) pre-soaking can realize the high-efficiency carbonation of recycled coarse aggregate,for modified recycled coarse aggregate with the method,water absorption is reduced by 23.03%,porosity is reduced by 44.06%,and the average pore diameter is 21.82 nm.The high-efficiency carbonation strengthening mechanism show that the pre-socked nano-SiO_(2) is bound to the hydration product Ca(OH)_(2) of the old mortar with nano-scale C-S-H,which can improve the CO_(2) absorption rate,accelerate the carbonation reaction,generate more stable CaCO_(3) and nano-scale silica gel,and bond to the dense three-dimensional network structure to realize the bidirectional enhancement of nano-materials and pressurized carbonation.It is concluded that the method of carbonation with nano-SiO_(2) pre-soaking is a novel high-efficiency carbonation modification of recycled coarse aggregate. 展开更多
关键词 recycled coarse aggregate pressurized carbonation high-efficiency carbonation NANO-SIO2 strengthening mechanism
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Effect of Modification Treatment on Chloride Ions Permeability and Microstructure of Recycled Brick-mixed Aggregate Concrete
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作者 何子明 申爱琴 +2 位作者 WANG Xiaobin WU Jinhua WANG Lusheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期728-737,共10页
The modification methods of pozzolan slurry combined with sodium silicate and silicon-based additive were respectively adopted to treat recycled coarse brick-mixed aggregate(RCBA)in this study.The compressive strength... The modification methods of pozzolan slurry combined with sodium silicate and silicon-based additive were respectively adopted to treat recycled coarse brick-mixed aggregate(RCBA)in this study.The compressive strength and chloride permeability resistance of recycled aggregate concrete(RAC)before and after modification treatment were tested,and the microstructure of RAC was analyzed by mercury intrusion porosimetry(MIP)and scanning electron microscopy(SEM).The results show that the physical properties of RCBA strengthened by modification treatment are improved,and the compressive strength and chloride permeability resistance of treated RAC are also significantly improved.The modification treatment optimizes the pore size distribution of RAC,which increases the number of gel pores and transition pores,and decreases the number of capillary pores and macro pores.The surface fractal dimension shows a significant correlation with chloride diffusion coefficient,indicating that the variation of chloride permeability of treated RAC is consistent with the microstructure evolution. 展开更多
关键词 recycled aggregate concrete modification treatment compressive strength chloride permeability resistance MICROSTRUCTURE
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"Three-in-One" Ecological Development and Efficient Utilization Model of Aggregates
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作者 Yunkai FAN Shichang XU +2 位作者 Qiangjie HUANG Yiyuan LU Ziyi WEI 《Asian Agricultural Research》 2024年第6期13-18,共6页
Green mining and the formation of an effective and efficient development model have become key issues that aggregates enterprises around the world need to solve urgently.On the basis of analyzing the development statu... Green mining and the formation of an effective and efficient development model have become key issues that aggregates enterprises around the world need to solve urgently.On the basis of analyzing the development status of aggregates industry in Xiluodu area,the paper studied the main problems faced in the construction of green aggregates mines at present,and proposed a"three-in-one"ecological,intelligent and efficient green mine construction model for"ecological development","green logistics"and"solid waste recycling"of aggregates.The study has certain theoretical value and practical significance for the construction of green aggregates mine in Xiluodu area. 展开更多
关键词 aggregateS ECOLOGICAL development EFFICIENT UTILIZATION
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Repair of Second-Generation Recycled Fine Aggregate of Waste Concrete from Freeze-Thaw Environment by Carbonation Treatment
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作者 Jie Huang Rongbin Jiang +1 位作者 Xiaobo Sun Yingyong Shuai 《Journal of Renewable Materials》 EI CAS 2024年第1期187-201,共15页
The reuse of waste recycled concrete from harsh environments has become a research hotspot in the field of construction.This study investigated the repair effect of carbonation treatment on second-generation recycled ... The reuse of waste recycled concrete from harsh environments has become a research hotspot in the field of construction.This study investigated the repair effect of carbonation treatment on second-generation recycled fine aggregate(SRFA)obtained from recycled fine aggregate concrete(RFAC)subjected to freeze-thaw(FT)cycles.Before and after carbonation,the properties of SRFA were evaluated.Carbonated second-generation recycled fine aggregate(CSRFA)at five substitution rates(0%,25%,50%,75%,100%)to replace SRFA was used to prepare carbonated second-generation recycled fine aggregate concrete(CSRFAC).The water absorption,porosity and mechanical properties of CSRFAC were tested,and its frost-resisting durability was evaluated.The results showed after carbonation treatment,the physical properties of SRFA was improved and met the requirements of II aggregate.The micro-hardness of the interfacial transition zone and attached mortar in CSRFA was 50.5%and 31.2%higher than that in SRFA,respectively.With the increase of CSRFA replacement rate,the water absorption and porosity of CSRFAC gradually decreased,and the mechanical properties and frost resistance of CSRFAC were gradually improved.Carbonation treatment effectively repairs the damage of SRFA caused by FT cycles and improves its application potential. 展开更多
关键词 Carbonation treatment REPAIR freeze-thaw cycles second-generation recycled fine aggregate
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Simulation of Fracture Process of Lightweight Aggregate Concrete Based on Digital Image Processing Technology
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作者 Safwan Al-sayed Xi Wang Yijiang Peng 《Computers, Materials & Continua》 SCIE EI 2024年第6期4169-4195,共27页
The mechanical properties and failure mechanism of lightweight aggregate concrete(LWAC)is a hot topic in the engineering field,and the relationship between its microstructure and macroscopic mechanical properties is a... The mechanical properties and failure mechanism of lightweight aggregate concrete(LWAC)is a hot topic in the engineering field,and the relationship between its microstructure and macroscopic mechanical properties is also a frontier research topic in the academic field.In this study,the image processing technology is used to establish a micro-structure model of lightweight aggregate concrete.Through the information extraction and processing of the section image of actual light aggregate concrete specimens,the mesostructural model of light aggregate concrete with real aggregate characteristics is established.The numerical simulation of uniaxial tensile test,uniaxial compression test and three-point bending test of lightweight aggregate concrete are carried out using a new finite element method-the base force element method respectively.Firstly,the image processing technology is used to produce beam specimens,uniaxial compression specimens and uniaxial tensile specimens of light aggregate concrete,which can better simulate the aggregate shape and random distribution of real light aggregate concrete.Secondly,the three-point bending test is numerically simulated.Thirdly,the uniaxial compression specimen generated by image processing technology is numerically simulated.Fourth,the uniaxial tensile specimen generated by image processing technology is numerically simulated.The mechanical behavior and damage mode of the specimen during loading were analyzed.The results of numerical simulation are compared and analyzed with those of relevant experiments.The feasibility and correctness of the micromodel established in this study for analyzing the micromechanics of lightweight aggregate concrete materials are verified.Image processing technology has a broad application prospect in the field of concrete mesoscopic damage analysis. 展开更多
关键词 Digital image processing lightweight aggregate concrete mesoscopic model numerical simulation fracture analysis bending beams
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Impact of wetting-drying cycles and acidic conditions on the soil aggregate stability of yellow‒brown soil
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作者 XIA Zhenyao NI Yuanzhen +2 位作者 LIU Deyu WANG Di XIAO Hai 《Journal of Mountain Science》 SCIE CSCD 2024年第6期2075-2090,共16页
Soil aggregate is the basic structural unit of soil,which is the foundation for supporting ecosystem functions,while its composition and stability is significantly affected by the external environment.This study was c... Soil aggregate is the basic structural unit of soil,which is the foundation for supporting ecosystem functions,while its composition and stability is significantly affected by the external environment.This study was conducted to explore the effect of external environment(wetting-drying cycles and acidic conditions)on the soil aggregate distribution and stability and identify the key soil physicochemical factors that affect the soil aggregate stability.The yellow‒brown soil from the Three Gorges Reservoir area(TGRA)was used,and 8 wetting-drying conditions(0,1,2,3,4,5,10 and 15 cycles)were simulated under 4 acidic conditions(pH=3,4,5 and 7).The particle size distribution and soil aggregate stability were determined by wet sieving method,the contribution of environmental factors(acid condition,wetting-drying cycle and their combined action)to the soil aggregate stability was clarified and the key soil physicochemical factors that affect the soil aggregate stability under wetting-drying cycles and acidic conditions were determined by using the Pearson’s correlation analysis,Partial least squares path modeling(PLS‒PM)and multiple linear regression analysis.The results indicate that wetting-drying cycles and acidic conditions have significant effects on the stability of soil aggregates,the soil aggregate stability gradually decreases with increasing number of wetting-drying cycles and it obviously decreases with the increase of acidity.Moreover,the combination of wetting-drying cycles and acidic conditions aggravate the reduction in the soil aggregate stability.The wetting-drying cycles,acidic conditions and their combined effect imposes significant impact on the soil aggregate stability,and the wetting-drying cycles exert the greatest influence.The soil aggregate stability is significantly correlated with the pH,Ca^(2+),Mg^(2+),maximum disintegration index(MDI)and soil bulk density(SBD).The PLS‒PM and multiple linear regression analysis further reveal that the soil aggregate stability is primarily influenced by SBD,Ca^(2+),and MDI.These results offer a scientific basis for understanding the soil aggregate breakdown mechanism and are helpful for clarifying the coupled effect of wetting-drying cycles and acid rain on terrestrial ecosystems in the TGRA. 展开更多
关键词 Yellow‒brown soil Wetting-drying cycles Acidic conditions Soil aggregate stability Soil disintegration
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TAX1BP1 and FIP200 orchestrate non-canonical autophagy of p62 aggregates for mouse neural stem cell maintenance
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作者 Yi-Fu Zhu Rong-Hua Yu +15 位作者 Shuai Zhou Pei-Pei Tang Rui Zhang Yu-Xin Wu Ran Xu Jia-Ming Wei Ying-Ying Wang Jia-Li Zhang Meng-Ke Li Xiao-Jing Shi Yu-Wei Zhang Guang-Zhi Liu Rick FThorne Xu Dong Zhang Mian Wu Song Chen 《Zoological Research》 SCIE CSCD 2024年第4期937-950,共14页
Autophagy plays a pivotal role in diverse biological processes,including the maintenance and differentiation of neural stem cells(NSCs).Interestingly,while complete deletion of Fip200 severely impairs NSC maintenance ... Autophagy plays a pivotal role in diverse biological processes,including the maintenance and differentiation of neural stem cells(NSCs).Interestingly,while complete deletion of Fip200 severely impairs NSC maintenance and differentiation,inhibiting canonical autophagy via deletion of core genes,such as Atg5,Atg16l1,and Atg7,or blockade of canonical interactions between FIP200 and ATG13(designated as FIP200-4A mutant or FIP200 KI)does not produce comparable detrimental effects.This highlights the likely critical involvement of the non-canonical functions of FIP200,the mechanisms of which have remained elusive.Here,utilizing genetic mouse models,we demonstrated that FIP200 mediates non-canonical autophagic degradation of p62/sequestome1,primarily via TAX1BP1 in NSCs.Conditional deletion of Tax1bp1 in fip200hGFAP conditional knock-in(cKI)mice led to NSC deficiency,resembling the fip200hGFAP conditional knockout(cKO)mouse phenotype.Notably,reintroducing wild-type TAX1BP1 not only restored the maintenance of NSCs derived from tax1bp1-knockout fip200hGFAP cKI mice but also led to a marked reduction in p62 aggregate accumulation.Conversely,a TAX1BP1 mutant incapable of binding to FIP200 or NBR1/p62 failed to achieve this restoration.Furthermore,conditional deletion of Tax1bp1 in fip200hGFAP cKO mice exacerbated NSC deficiency and p62 aggregate accumulation compared to fip200hGFAP cKO mice.Collectively,these findings illustrate the essential role of the FIP200-TAX1BP1 axis in mediating the non-canonical autophagic degradation of p62 aggregates towards NSC maintenance and function,presenting novel therapeutic targets for neurodegenerative diseases. 展开更多
关键词 Non-canonical autophagy TAX1BP1 FIP200 P62 aggregateS Neural stem cell
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Calcium carbonate promotes the formation and stability of soil macroaggregates in mining areas of China
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作者 Junyu Xie Jianyong Gao +7 位作者 Hanbing Cao Jiahui Li Xiang Wang Jie Zhang Huisheng Meng Jianping Hong Tingliang Li Minggang Xu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期1034-1047,共14页
We studied changes in the concentrations of aggregate-cementing agents after different reclamation times and with different fertilization regimes,as well as the formation mechanism of aggregates in reclaimed soil,to p... We studied changes in the concentrations of aggregate-cementing agents after different reclamation times and with different fertilization regimes,as well as the formation mechanism of aggregates in reclaimed soil,to provide a theoretical basis for rapid reclamation of soil fertility in the subsidence area of coal mines in Shanxi Province,China.In this study,soil samples of 0–20 cm depth were collected from four fertilization treatments of a longterm experiment started in 2008:no fertilizer (CK),inorganic fertilizer (NPK),chicken manure compost (M),and50%inorganic fertilizer plus 50%chicken manure compost (MNPK).The concentrations of cementing agents and changes in soil aggregate size distribution and stability were analysed.The results showed that the formation of>2 mm aggregates,the aggregate mean weight diameter (MWD),and the proportion of>0.25 mm water-stable aggregates (WR_(0.25)) increased significantly after 6 and 11 years of reclamation.The concentration of organic cementing agents tended to increase with reclamation time,whereas free iron oxide (Fed) and free aluminium oxide(Ald) concentrations initially increased but then decreased.In general,the MNPK treatment signi?cantly increased the concentrations of organic cementing agents and CaCO_(3),and CaCO_(3) increased by 60.4%at 11 years after reclamation.Additionally,CaCO_(3) had the greatest effect on the stability of aggregates,promoting the formation of>0.25 mm aggregates and accounting for 54.4%of the variance in the proportion and stability of the aggregates.It was concluded that long-term reclamation is bene?cial for improving soil structure.The MNPK treatment was the most effective measure for increasing maize grain yield and concentration of organic cementing agents and CaCO_(3). 展开更多
关键词 reclamation time manure combined with inorganic fertilizer soil aggregate stability cementing agents CaCO_(3)
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Effect of Lateritic Stone Aggregate and Coconut Husk Fiber on the Properties of Concrete
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作者 Edmund Borbi Humphrey Danso Emmanuel Appiah-Kubi 《Open Journal of Civil Engineering》 2024年第2期240-257,共18页
Natural stone aggregate forms the bulk volume of concrete and has contributed to the increased cost of concrete production. This has led to the search for alternate aggregates such as lateritic stone for concrete prod... Natural stone aggregate forms the bulk volume of concrete and has contributed to the increased cost of concrete production. This has led to the search for alternate aggregates such as lateritic stone for concrete production. This paper investigates the engineering properties of concrete produced with lateritic aggregate (LA) as the coarse aggregate replacement and coconut husk fibre (CHF) as reinforcement. Natural stone aggregate was replaced by LA at 0%, 10%, 20%, 30%, 40%, and 50%, with 0.25% constant CHF by weight. A mix proportion of 1:1.5:3 with a water-cement ratio of 0.6 was used for producing concrete. A total of 162 specimens (90 cubes and 72 beams) were prepared and tested at the 7, 14, 21, and 28 days of curing. The highest compressive strength was 43.36 N/mm2 (10% LA replacement) as compared to the control of 41.51 N/mm2. The 10% LA replacement obtained the highest flexural strength of 5.35 N/mm2 as compared with the 5.29 N/mm2 for the control. The water absorption of the concrete increased from 2.8% (control) to 3.57% (50% replacement LA). Scanning electron microscopy (SEM) revealed micro gaps between CHF and LA concrete. The study, therefore, concludes that the use of LA and CHF positively influenced the strength properties of concrete. 10% LA replacement of coarse aggregate and 0.25% CHF is recommended to practitioners for use. 展开更多
关键词 CONCRETE Coarse aggregate Compressive Strength Flexural Strength Natural Stone aggregate SEM
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AGGREGATE SPECIAL FUNCTIONS TO APPROXIMATE PERMUTING TRI-HOMOMORPHISMS AND PERMUTING TRI-DERIVATIONS ASSOCIATED WITH A TRI-ADDITIVEψ-FUNCTIONAL INEQUALITY IN BANACH ALGEBRAS
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作者 Safoura Rezaei ADERYANI Azam AHADI +1 位作者 Reza SAADATI Hari M.SRIVASTAVA 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期311-338,共28页
In this paper,we define a new class of control functions through aggregate special functions.These class of control functions help us to stabilize and approximate a tri-additiveψ-functional inequality to get a better... In this paper,we define a new class of control functions through aggregate special functions.These class of control functions help us to stabilize and approximate a tri-additiveψ-functional inequality to get a better estimation for permuting tri-homomorphisms and permuting tri-derivations in unital C*-algebras and Banach algebras by the vector-valued alternative fixed point theorem. 展开更多
关键词 permuting tri-homomorphism in Banach algebra permuting tri-derivation on C*-algebra fixed point theorem Ulam-Hyers-Rassias stability aggregate special functions tri-additiveψ-functional inequality
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Substitution of Aggregates in Concrete and Mortar with Coltan Mining Waste: Mechanical, Environmental, and Economic Impact Case Study
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作者 Alinabiwe Nyamuhanga Ally Élodie Ruffine Zang +5 位作者 Masika Muhiwa Grâce Manjia Marcelline Blanche Ursula Joyce Merveilles Pettang Nana Ngapgue François Bella Nabil Chrispin Pettang 《Journal of Minerals and Materials Characterization and Engineering》 2024年第2期139-163,共25页
The mining process involves drilling and excavation, resulting in the production of waste rock and tailings. The waste materials are then removed and stored in designated areas. This study aims to evaluate the mechani... The mining process involves drilling and excavation, resulting in the production of waste rock and tailings. The waste materials are then removed and stored in designated areas. This study aims to evaluate the mechanical strength and the environmental and economic impact of using Coltan Mining Waste (CMW) as a substitute for aggregates in concrete and mortar production. To achieve this, the CMW needs to be characterised. The Dreux Gorisse method was primarily used to produce concrete with a strength of 20 MPa at 28 days. The mortars, on the other hand, were formulated according to the NF P 18-452 standard. The environmental impact of using CMW as substitutes for natural aggregates in the production of concrete and mortar was analysed using SimaPro software. The results showed that mortars and concrete made with CMW have comparable compressive strengths to the reference mortar and concrete;reduce the negative impact on ecosystem quality, human health, resources, and climate change. It has also been shown that the substitution of aggregates by CMW reduces the cost of concrete and mortar as a function of the distance from the aggregate footprint. 展开更多
关键词 aggregate Coltan Mining Waste CONCRETE MORTAR Mechanical Strength Life Cycle Analysis
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